Yamaha YZFR6X(C) 2008 Service Manual page 229

• Valve-stem-to-valve-guide clearance
Out of specification → Replace the valve
guide.
• Valve-stem-to-valve-guide clearance =
Valve guide inside diameter "a" -
Valve stem diameter "b"
Valve-stem-to-valve-guide clear-
ance (intake)
0.010–0.037
0.0015 in)
Limit
0.080 mm (0.0032 in)
Valve-stem-to-valve-guide clear-
ance (exhaust)
0.025–0.052
0.0020 in)
Limit
0.095 mm (0.0037 in)
2. Replace:
• Valve guide
NOTE:
To ease valve guide removal and installation,
and to maintain the correct fit, heat the cylinder
head to 100 °C (212 °F) in an oven.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the valve guide with the valve
guide remover "1".
VALVES AND VALVE SPRINGS
mm (0.0004–
mm (0.0010–
5-20
b. Install the new valve guide with the valve
guide installer "2" and valve guide remover
"1".
Valve guide position
15.80 mm–16.20 mm (0.622–
0.638 in)
a. Valve guide position
c. After installing the valve guide, bore the
valve guide with the valve guide reamer "3"
to obtain the proper valve-stem-to-valve-
guide clearance.
NOTE:
After replacing the valve guide, reface the
valve seat.